Thanks to technological advancements, the development of glass materials has reached a highly mature state, giving rise to various types of glass that have different physical properties and applications, such as safety glass, tempered glass, thermally stable glass, low-expansion glass, and laminated glass, to name only a few. These new types of glass have enhanced the quality of our daily lives but also form blind spots in terms of safety. For instance, doors and windows (including car windows) made of tempered glass, which cannot be rapidly smashed without a proper tool, tend to hinder escape from a house, car, or other glass-enclosed environment where an accident (e.g., a fire or car crash) takes place. In addition, the sharp broken pieces of such tempered-glass obstacles are hard to remove and may therefore delay escape or rescue, leading to tragic consequences.
Take tempered glass and safety glass, which have high structural strength and are widely used nowadays in public transportation (e.g., busses and streetcars) and buildings, for example. Such a glass material is so difficult to smash that a police officer, firefighter, or rescue team member striking it with a hammer, bat, or other heavy object may be injured by the massive recoil of the striking tool in use. Generally speaking, only by hitting the glass material perpendicularly and vigorously with a pointed heavy object can the cohesive force in the glass material be effectively reduced to such extent that the glass material eventually breaks. Currently, referring to FIG. 1, the market is supplied with a portable tool 11 (e.g., a baton or flashlight) for use by the police and the fire departments to smash glass obstacles, wherein the tool 11 is mounted with a smashing cone 10. When a police officer or firefighter carrying out an emergency rescue operation or raid encounters an obstacle 12 made of strong glass (e.g., the windscreen or a window of a car), he or she can take out the tool 11 immediately and hit the glass obstacle 12 with the smashing cone 10 in order to reduce the cohesive force within the glass obstacle 12, thereby forming a breaking point in, and consequently shattering, the glass obstacle 12 to facilitate the rescue or attack.
In use, however, the tool 11 leaves plenty of room for improvement. One major drawback lies in the fact that the smashing cone 10 is typically fixed at one end (e.g., the front or rear end) of the tool 11 in order to be portable along with the tool 11, and that therefore one who uses the tool 11 in an emergency rescue operation or raid must hold the tool 11 with the thumb facing themselves (see FIG. 1) in order to apply a force to the smashing cone 10 and hit the glass obstacle 12 repeatedly. Nevertheless, the way the tool 11 is held makes it difficult not only for the user to exert a force on the smashing cone 10, but also for the user to strike precisely the same spot on the glass obstacle 12 while moving the smashing cone 10 back and forth. As a result, the cohesive force within the glass obstacle 12 may stay intact even though the user has made great physical efforts, and failure to smash the glass obstacle 12 in time may bring about failure of the intended rescue or attack.
To overcome the foregoing drawbacks (i.e., the bulkiness and hence unsatisfactory portability of the tool 11, and the difficulty of hitting precisely the same spot on the glass obstacle 12 with the smashing cone 10), a novel expandable baton 2 as shown in FIG. 2 was developed. The expandable baton 2 is compact in size, can be easily carried around by a police officer or firefighter for self-defense, and can be expanded whenever needed in an emergency rescue or attack. Simply by holding the handle of the expandable baton 2, a user can apply a force to precisely the same spot on a robust glass obstacle over and over again through the smasher 4 at the front end of the expandable baton 2, in order for the smasher 4 to build up a striking force large enough to dissolve the cohesive force in the glass obstacle. As shown in FIG. 2, the expandable baton 2 includes an outer shaft 21 and at least one inner shaft 22. The outer shaft 21 and the inner shaft 22 form the basic structure of the expandable baton 2. The rear section of the outer shaft 21 forms a handle to be gripped by a user. The outer diameter of the inner shaft 22 is smaller than the inner diameter of the outer shaft 21 so that the inner shaft 22 can be moved, and thus mounted, into the outer shaft 21 through the rear end of the outer shaft 21. In addition, the configuration of the rear end portion 22a of the inner shaft 22 matches the configuration of a portion of the outer shaft 21 that is adjacent to the front end portion 21a of the outer shaft 21. For example, the rear end portion 22a of the inner shaft 22 flares a little while the front end portion 21a of the outer shaft 21 converges slightly to enable engagement between the two end portions. When the inner shaft 22 is displaced outward of the front end portion 21a of the outer shaft 21 such that the rear end portion 22a of the inner shaft 22 reaches a position in the outer shaft 21 that is adjacent to the front end portion 21a of the outer shaft 21, the outer wall of the rear end portion 22a of the inner shaft 22 is engaged with an inner wall portion of the outer shaft 21 that is adjacent to the front end portion 21a of the outer shaft 21. As a result, the entire inner shaft 22 is exposed from the front end portion 21a of the outer shaft 21 except for the portion adjacent to the rear end portion 22a of the inner shaft 22, which portion is now secured in the outer shaft 21. Conversely, when the inner shaft 22 is stored in the outer shaft 21, the rear end portion 22a of the inner shaft 22 is secured by an engaging member 21b in the rear end of the outer shaft 21, leaving only the front end of the inner shaft 22 exposed from the front end portion 21a of the outer shaft 21.
Referring to FIG. 3A in conjunction with FIG. 2, the smasher 4 is provided at the front end of the inner shaft 22 (or the front end of the innermost inner shaft 22 if the expandable baton 2 has several inner shafts 22) and includes a base 40, an eccentric spring 413, an impact block 43, a compression spring 44, and a smashing rod 45. The base 40 is coupled to the front end of the inner shaft 22 such that the base 40 and the inner shaft 22 form a single unit. An impact groove 41, a tapering groove 411, an aligning groove 412, and a compression force application groove 42 are sequentially formed, in a front-to-rear direction, in the base 40 and the front end of the inner shaft 22 and are in communication with one another. The front end of the base 40 is formed with an aperture 410. The aperture 410 is in communication sequentially with the impact groove 41, the tapering groove 411, the aligning groove 412, and the compression force application groove 42 and has a smaller diameter than the impact groove 41. The tapering groove 411 extends taperingly from the rear end of the impact groove 41 to the front end of the aligning groove 412, and the wall of the tapering groove 411 forms a first tapering pressing surface 4110. The diameter of the aligning groove 412 is smaller than those of the impact groove 41 and of the compression force application groove 42.
As shown in FIG. 3A, the impact block 43 is movably positioned in the compression force application groove 42. The front end of the impact block 43 can be pressed against the wall of the compression force application groove 42 (e.g., a portion of the compression force application groove 42 that is adjacent to the aligning groove 412) and is concavely provided with a striking groove 430. The striking groove 430 corresponds to the aligning groove 412 and has a smaller diameter than the aligning groove 412. The compression spring 44 is positioned in the compression force application groove 42 and has its two ends pressed respectively against the rear end of the impact block 43 and a wall portion of the compression force application groove 42 that is away from the aligning groove 412, in order to push the impact block 43 toward the aligning groove 412. To facilitate description of the structural features and striking principle of the smashing rod 45, the smashing rod 45 is hereinafter divided into a front section 450, a middle section 451, and a rear section 452. The front section 450 of the smashing rod 45 is formed with a smashing cone 4501. The middle section 451 matches the aligning groove 412 in diameter, and a wall portion of the middle section 451 that is adjacent to the rear section 452 forms a second tapering pressing surface 453. Normally, the axis of the smashing rod 45 is offset from the axis of the impact block 43 such that the rear end of the rear section 452 of the smashing rod 45 is pressed against the front end of the impact block 43 to prevent the rear section 452 of the smashing rod 45 from extending into the striking groove 430. Thus, with the front end of the impact block 43 pushing back at the rear end of the rear section 452 of the smashing rod 45, the smashing rod 45 is positioned in the impact groove 41, the tapering groove 411, and the aligning groove 412, with the smashing cone 4501 exposed from the front end of the smasher 4 through the aperture 410.
With continued reference to FIG. 3A, the eccentric spring 413 is mounted around the periphery of the middle section 451 of the smashing rod 45 and is positioned in the impact groove 41 and the tapering groove 411. The eccentric spring 413 has its two ends pressed respectively against a portion of the smashing rod 45 that is adjacent to the front section 450 and the wall of the tapering groove 411 (i.e., the first tapering pressing surface 4110), in order to push the front section 450 of the smashing rod 45 outward of the aperture 410, thereby exposing the smashing cone 4501 of the front section 450 of the smashing rod 45 from the front end of the smasher 4. The elastic force of the eccentric spring 413 must be smaller than that of the compression spring 44 so that, as soon as the rear section 452 of the smashing rod 45 is in alignment with the striking groove 430 (see FIG. 3B), the impact block 43 will strike the rear end of the rear section 452 of the smashing rod 45 under the action of the compression spring 44, and when the smashing cone 4501 of the front section 450 of the smashing rod 45 completes the intended striking and smashing action, the eccentric spring 413 will render the axis of the smashing rod 45 offset from the axis of the impact block 43, thereby moving the rear end of the rear section 452 of the smashing rod 45 away from the striking groove 430 and back to the position shown in FIG. 3A, i.e., pressed against the front end of the impact block 43 to wait for the next striking and smashing action to be performed.
Referring to FIGS. 3A and 3B in conjunction with FIG. 2, when a user holding the expandable baton 2 presses the smashing cone 4501 forcibly against a glass obstacle (e.g., a piece of tempered glass), the smashing rod 45 is gradually displaced toward the compression force application groove 42. When the second tapering pressing surface 453 of the wall of the middle section 451 of the smashing rod 45 is pressed against the first tapering pressing surface 4110, the middle section 451 of the smashing rod 45 begins to be guided by the aligning groove 412 into alignment with the axis of the impact block 43. Now that the middle section 451 of the smashing rod 45 matches the aligning groove 412 in diameter, the instant at which the middle section 451 becomes perfectly aligned with the striking groove 430 (i.e., enters the state shown in FIG. 3B), the rear section 452 of the smashing rod 45 thrusts into the striking groove 430, allowing the huge elastic force stored in the compression spring 44 to push the impact block 43 outward. The impact block 43 will in turn strike the rear end of the smashing rod 45, thereby driving the smashing cone 4501 at the front end of the smashing rod 45 to smash the glass obstacle vigorously. Thus, by equipping the expandable baton 2 with the smasher 4, the functions and applications of the expandable baton 2 are increased.
However, the overall length of the expandable baton 2 in the collapsed state (generally 20 cm or so) makes it difficult to put and store, let alone carry, the expandable baton 2 in a pocket of a user's upper-body garment or trousers in order to use the expandable baton 2 whenever needed. In addition, the pointed structure of the smashing cone 4501 of the front section 450 of the smashing rod 45 must be covered because the elastic forces applied to the smashing rod 45 by the eccentric spring 413 and by the compression spring 44 will keep the smashing cone 4501 exposed from the front end of the smasher 4. If the smashing cone 4501 is left uncovered, one who carries or is using the expandable baton 2 is very likely to be punctured or scratched by the smashing cone 4501, or injure people nearby, or cause damage to neighboring objects.
The issue to be addressed by the present invention, therefore, is to design a novel pen structure having a glass smasher. It is desirable that the structure of a glass smasher is applied to one end of a pen in a way that ensures structural compactness, so a police officer or firefighter not only can carry the assembly with them safely for the purpose of writing or drawing, but also can take the assembly swiftly out of a pocket for use during an emergency rescue operation or raid. It is also desirable that the smashing cone of the front section of a smashing rod in the glass smasher can be rapidly exposed from the end of the pen by the user removing a smashing cone cover from the front end of the glass smasher, and that the user can then control the assembly with ease while holding the pen body. More specifically, the user can hit the same spot on a robust glass obstacle repeatedly with the smashing cone in order to build up a striking force large enough to reduce the cohesive force in the glass obstacle, thereby breaking the glass obstacle effectively.